Parameter | Estimate for all patients (95% CI) n = 11 621 | Heterogeneity (I2), % | Estimate for patients with noncancer illness (95% CI) n = 2457 | Heterogeneity (I2), % | Estimate for patients with cancer (95% CI) n = 6927 | Heterogeneity (I2), % | p value† |
---|---|---|---|---|---|---|---|
DOR | 8.21 (6.21–10.87) | 0 | 5.94 (4.57–7.81) | 0 | 10.69 (7.06–16.19) | 28.0 | 0.02 |
LR+ | 3.4 (2.8–4.1) | 0 | 2.7 (2.1–3.6) | 0 | 4.2 (2.9–6.0) | 17.4 | 0.06 |
LR− | 0.41 (0.32–0.54) | 0 | 0.53 (0.46–0.61) | 0 | 0.41 (0.32–0.53) | 39.0 | 0.09 |
Sensitivity, % | 67.0 (55.7–76.7) | 88.7 | 60.7 (52.6–68.1) | 40.0 | 66.4 (54.1–76.8) | 89.2 | 0.4 |
Specificity, % | 80.2 (73.3–85.6) | 96.5 | 75.9 (67.6–82.6) | 92.7 | 84.3 (77.6–89.3) | 95.0 | 0.08 |
PPV, % | 37.1 (30.2–44.6) | 89.5 | 31.3 (25.0–38.3) | 67.8 | 46.8 (36.4–57.5) | 90.1 | 0.02 |
NPV, % | 93.1 (91.0–94.8) | 86.4 | 93.2 (90.5–95.2) | 68.6 | 92.4 (87.3–95.6) | 94.3 | 0.7 |
AUC | 0.81 (0.78–0.84) | NA | 0.77 (0.74–0.8) | NA | 0.83 (0.79–0.87) | NA | 0.02 |
Note: AUC = area under the ROC curve, CI = confidence interval, DOR = diagnostic odds ratio, LR+ = positive likelihood ratio, LR− = negative likelihood ratio, NA = not applicable, NPV = negative predictive value, PPV = positive predictive value.
↵* Parameter estimates for all patients (16 studies, 17 cohorts) used hierarchical summary receiver operating characteristic (sROC) models. For cancer studies involving patients with cancer (5), studies involving patients with noncancer illness (9, 10 cohorts) and for all measures of heterogeneity (including for all studies combined), analyses used univariable models (see text for details). Heterogeneity measures are not available for AUC, which is derived from DOR.
↵† The z test was used for p values to compare studies involving patients with cancer with studies involving patients with noncancer illness.